This invention relates to the field of controls, and particularly to an improved digital control for electronic apparatus.
As electronic equipment has become increasingly miniaturized, manual controls have become more of a problem. Decreasing the size of controls such as potentiometers increases cost and causes more failures due to dust and wear. Eventually, a limiting point is reached in size reduction. Thus, a new technology rather than mere miniaturization of the old technology was required. Solid state electronic devices and logic circuitry were probably first used for replacing potentiometers as in volume control circuits in response to the desire for remote television controls. In these devices, depressing a button or buttons on a hand-held device sends a signal to the television console. Upon being received, this acoustical or electromagnetic signal is typically translated into a voltage for causing rotation of the shaft of a turret-type tuner switch by a motor or stepping relay. Control of volume has also been accomplished by the transmission and reception of a similar signal with an on-off function provided at the minimum volume setting. In miniature devices such as pocket pagers, the size of controls is even more of a problem since other functions besides simply running volume up and down and turning the receiver off are desirable. It is particularly desirable to have a brief delay period during which the user receives some type of warning before the apparatus turns off or another function is enabled.